RTF Input: Substitute a dummy image for WMF images in the RTF document

src/calibre/ebooks/rtf/input.py

@@ -159,11 +159,31 @@ class RTFInput(InputFormatPlugin):
         return imap
 
     def convert_image(self, name):
-        from calibre.utils.magick import Image
-        img = Image()
-        img.open(name)
+        try:
+            return self.rasterize_wmf(name)
+        except:
+            self.log.exception('Failed to convert WMF image %r'%name)
+        return self.replace_wmf(name)
+
+    def replace_wmf(self, name):
+        from calibre.ebooks import calibre_cover
+        data = calibre_cover('Conversion of WMF images is not supported',
+            'Use Microsoft Word or OpenOffice to save this RTF file'
+            ' as HTML and convert that in calibre.', title_size=36,
+            author_size=20)
         name = name.replace('.wmf', '.jpg')
-        img.save(name)
+        with open(name, 'wb') as f:
+            f.write(data)
+        return name
+
+    def rasterize_wmf(self, name):
+        from calibre.utils.wmf import extract_raster_image
+        with open(name, 'rb') as f:
+            data = f.read()
+        data = extract_raster_image(data)
+        name = name.replace('.wmf', '.jpg')
+        with open(name, 'wb') as f:
+            f.write(data)
         return name
 
 

src/calibre/utils/wmf/__init__.py

@@ -5,5 +5,52 @@ __license__   = 'GPL v3'
 __copyright__ = '2011, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
+import glob
+
+from calibre.constants import plugins, iswindows, filesystem_encoding
+from calibre.ptempfile import TemporaryDirectory
+from calibre import CurrentDir
+from calibre.utils.magick import Image, PixelWand
+
+class Unavailable(Exception):
+    pass
+
+class NoRaster(Exception):
+    pass
+
+def extract_raster_image(wmf_data):
+    try:
+        wmf, wmf_err = plugins['wmf']
+    except KeyError:
+        raise Unavailable('libwmf not available on this platform')
+    if wmf_err:
+        raise Unavailable(wmf_err)
+
+    if iswindows:
+        import sys, os
+        appdir = sys.app_dir
+        if isinstance(appdir, unicode):
+            appdir = appdir.encode(filesystem_encoding)
+        fdir = os.path.join(appdir, 'wmffonts')
+        wmf.set_font_dir(fdir)
+
+    data = ''
+
+    with TemporaryDirectory('wmf2png') as tdir:
+        with CurrentDir(tdir):
+            wmf.render(wmf_data)
+
+            images = list(sorted(glob.glob('*.png')))
+            if not images:
+                raise NoRaster('No raster images in WMF')
+            data = open(images[0], 'rb').read()
+
+    im = Image()
+    im.load(data)
+    pw = PixelWand()
+    pw.color = '#ffffff'
+    im.rotate(pw, 180)
+
+    return im.export('png')
 
 

src/calibre/utils/wmf/wmf.c

@@ -4,6 +4,7 @@
 
 #include <libwmf/api.h>
 #include <libwmf/svg.h>
+//#include <libwmf/gd.h>
 
 typedef struct {
     char *data;
@@ -13,7 +14,7 @@ typedef struct {
 
 //This code is taken mostly from the Abiword wmf plugin
 
-
+// Buffer read {{{
 // returns unsigned char cast to int, or EOF
 static int wmf_WMF_read(void * context) {
     char c;
@@ -22,11 +23,11 @@ static int wmf_WMF_read(void * context) {
 	if (info->pos == info->len)
 		return EOF;
 
-	c = info->data[pos];
+	c = info->data[info->pos];
 
 	info->pos++;
 
-	return (int)c;
+	return (int)((unsigned char)c);
 }
 
 // returns (-1) on error, else 0
@@ -44,8 +45,17 @@ static long wmf_WMF_tell(void * context) {
 
 	return (long) info->pos;
 }
+// }}}
 
 
+char _png_name_buf[100];
+char *wmf_png_name(void *ctxt) {
+    int *num = (int*)ctxt;
+    *num = *num + 1;
+    snprintf(_png_name_buf, 90, "%04d.png", *num);
+    return _png_name_buf;
+}
+
 #define CLEANUP if(API) { if (stream) wmf_free(API, stream); wmf_api_destroy(API); };
 
 static PyObject *
@@ -66,9 +76,9 @@ wmf_render(PyObject *self, PyObject *args) {
 
 	unsigned int max_width  = 1600;
 	unsigned int max_height = 1200;
-	unsigned long max_flags = 0;
 
 	static const char* Default_Description = "wmf2svg";
+    int fname_counter = 0;
 
 	wmf_error_t err;
 
@@ -125,6 +135,8 @@ wmf_render(PyObject *self, PyObject *args) {
 	ddata->Description = (char *)Default_Description;
 
 	ddata->bbox = bbox;
+    ddata->image.context = (void *)&fname_counter;
+    ddata->image.name = wmf_png_name;
 
 	wmf_display_size(API, &disp_width, &disp_height, 96, 96);
 
@@ -156,9 +168,9 @@ wmf_render(PyObject *self, PyObject *args) {
 		ddata->height = (unsigned int) ceil ((double) wmf_height);
 	}
 
-	ddata->flags |= WMF_SVG_INLINE_IMAGES;
-
-	ddata->flags |= WMF_GD_OUTPUT_MEMORY | WMF_GD_OWN_BUFFER;
+    // Needs GD
+	//ddata->flags |= WMF_SVG_INLINE_IMAGES;
+	//ddata->flags |= WMF_GD_OUTPUT_MEMORY | WMF_GD_OWN_BUFFER;
 
     err = wmf_play(API, 0, &(bbox));
 
@@ -178,11 +190,32 @@ wmf_render(PyObject *self, PyObject *args) {
     return ans;
 }
 
+#ifdef _WIN32
+void set_libwmf_fontdir(const char *);
+
+static PyObject *
+wmf_setfontdir(PyObject *self, PyObject *args) {
+    char *path;
+    if (!PyArg_ParseTuple(args, "s", &path))
+        return NULL;
+    set_libwmf_fontdir(path);
+
+    Py_RETURN_NONE;
+}
+#endif
+
+
+
 
 static PyMethodDef wmf_methods[] = {
     {"render", wmf_render, METH_VARARGS,
-        "render(path) -> Render wmf as svg."
+        "render(data) -> Render wmf as svg."
     },
+#ifdef _WIN32
+    {"set_font_dir", wmf_setfontdir, METH_VARARGS,
+        "set_font_dir(path) -> Set the path to the fonts dir on windows, must be called at least once before using render()"
+    },
+#endif
 
     {NULL}  /* Sentinel */
 };